1. Field of the Invention
The present invention generally pertains to an integrated device including a cable reel and combined switch systems for mounting in a steering wheel of an automobile.
2. Description of Background Information
Nowadays, a steering wheel usually contains an airbag and an inflator for inflating the airbag. The inflator is electrically connected to electrical circuitry mounted on a panel of an automobile via a cable reel known as a rotary connector. As shown in FIGS. 1 and 2, the cable reel includes an outer cylindrical body which constitutes a fixed body 2. The fixed body 2 is connected to combination switch bodies 3 linked to a steering column 4. The cable reel 1 also includes a mobile body 5, which constitutes an inner cylindrical body. The mobile body 5 is mounted into the fixed body 2 in a freely rotatable manner, and is further fitted into a steering wheel so as to form a hollow torus. The hollow torus contains a flat cable 6 arranged in a spiral. One end of the flat cable 6 is fixed to the fixed body 2, and the other end thereof is fixed to the mobile body 5, so that the signals passing through the flat cable 6 can be transmitted to outside. When the steering wheel is turned, the mobile body is rotated correspondingly clockwise or counter-clockwise. The flat cable 6 can follow the above rotation by winding or unwinding its spirals.
In a known steering wheel system, which includes a cable reel 1, combination switch bodies 3, a steering wheel and a steering column 4, a mobile body 5 mounted in the cable reel 1 is fixed to the lower end (as viewed in FIG. 2) of the steering wheel through a lobe (not shown in the figures). The fixed body 2, into which the mobile body 5 is mounted in a freely rotatable manner, is fixed on the upper face (as viewed in FIG. 2) of the combination switch bodies 3, and the combination switch bodies 3 are fixed to the steering column 4. The combination switch body 3 located on the right-hand side of the steering column (FIG. 1) carries a turn indicator-signal unit 7 (winker or blinker unit) which includes a turn indicator-signal housing 7a containing turn indicator-signal circuitry 7b such as a turn indicator-signal switch (winker switch). Likewise, the combination switch body 3 located on the left-hand side of the steering column (FIG. 1) carries a lighting unit 8 which includes a lighting housing 8a containing lighting circuitry 8b such as a light switch. The turn indicator-signal unit 7 and the lighting unit 8 further include a turn indicator-signal lever 7c and a lighting lever 8c, both projecting outwardly from the respective housings 7a and 8a. 
One of the combination switch bodies 3 and a steering shaft 9 form a space under the cable reel 1. Accordingly, a cancel cam 10 and an encoder (steering angle sensor) 11 can be installed in this space, and mounted on the steering shaft 9.
However, in the above construction, the turn indicator-signal unit 7, lighting unit 8, cable reel 1, cancel cam 10 and encoder 11 are provided as corresponding individual units, and assembled together at a subsequent stage. Accordingly, each unit requires a housing and mounting means, e.g. bolts, by which it is linked to the other units. As a result, the number of parts used tends to increase greatly.
Further, the housing for these units tends to increase the height, diameter and weight of the construction, as does the configuration in which the cable reel 1 is mounted on the combination switch bodies 3. Moreover, the above units are typically supplied by different manufacturers. A sufficient degree of clearance must then be provided when these units are assembled. As a result, a space, otherwise unnecessary, must be taken into account, and the construction becomes more voluminous.
An object of the present invention is therefore to provide a structure requiring no unit-by-unit assembling. According to another aspect of the present invention, the structure of the integrated connector device is reduced to a minimum size and weight, by modifying the mounting position of the cable reel.
To this end, according to one aspect of the present invention, there is provided an integrated connector device including a cable reel and combined switch system. The integrated connector device further includes a base shell including: a top wall portion with a central through-hole; an outer sidewall portion extending downwardly from the top wall portion and having first and second lever notches; and first and second partitions respectively provided at a predetermined distance from the outer sidewall portion. The base shell has a central axis.
The cable reel of the present invention also includes a fixed body and a mobile body, and has a central axis.
The combined switch systems of the present invention may also include a turn indicator signal system and a lighting system respectively including turn indicator signal and lighting levers.
The cable reel is fitted into the base shell by joining the respective central axis, such that the fixed body is fitted between the first and second partitions, the turn indicator-signal system being fitted between the outer sidewall portion and the first partition, the lighting system is fitted between the outer sidewall portion and the second partition, and the turn indicator-signal and lighting levers are extended outwardly through the first and second lever notches.
Preferably, the mobile body of the cable reel contained in the base shell includes an upper portion, and the upper portion carries a cancel cam integrally formed therewith.
According to a further aspect of the present invention, the mobile body of the cable reel contained in the base shell includes a top wall portion, and the fixed body of the cable reel includes an outer sidewall portion. The top wall portion of the mobile body carries a main scale portion integrally formed therewith. There is provided an encoder between the outer sidewall portion of the fixed body and the outer sidewall portion of the base shell, but spaced from the positions where the turn indicator-signal and lighting systems are located, such that the encoder can detect the position of the main scale portion.
Suitably, the cable reel and the base shell are adapted to be joined to a steering shaft having a central axis, such that the central axes of the cable reel and base shell are the same as that of the steering shaft, and the turn indicator-signal system and the lighting system are placed at a predetermined position with respect to the central axis of the steering shaft.
As mentioned above, the present invention includes a base shell which contains a turn indicator-signal system including necessary functional parts, as well as a lighting system including necessary functional parts. These functional parts are no longer stored in separate housings as in the prior art, but incorporated into the base shell as an integral system thereof The space necessary for the separate housings can thus be eliminated. Further, the cable reel is fitted into the inner side (central axis side of the base shell) of the first and second partitions of the base shell, so that the height and width size of the integrated connector device is reduced, and the entire structure of the device becomes compact.
Further, the turn indicator-signal system and the lighting system are not stored in separate housings as a unitary entity, so that functional parts for these systems can be added or modified very easily.
Furthermore, when the above systems are adopted, it is no longer necessary to rely on the separate unitary entities which are often manufactured by different parts-makers. The space usually necessary for clearance between these unitary entities of different origins can thus be obviated, and the whole device can be miniaturized.
Further yet, the integrated connector device is configured such that the central axis of the base shell and that of the steering shaft are brought together, so that all members or systems to be incorporated into the base shell can be installed very easily at predetermined positions with respect to the central axis.
The encoder preferably includes a printed circuit board, and a sensor system connected thereto which includes a light-emitting element and a light-receiving element. A main scale is provided in a space formed between the light-emitting element and the light-receiving element, and rotated therein in conjunction with the mobile body, so that the steering angle can be detected. All these members are integrally molded in a resin.
The cancel cam and the main scale are integrally formed with the mobile body of the cable reel. Further, the encoder is disposed between the fixed body and the base shell, in ways that the structure of the integrated connector device is simplified and rendered more compact.